which are important for the project. The article quotes Dr Nagi Elabbasi, principal engineer at Veryst Engineering, a consulting firm that offers simulation expertise to customers. Elabbasi states: ‘The application development process itself is very easy and user friendly. In the applications, you have access to extensive Java functionality.’ This allows Veryst to link applications to its material library, PolyUMod, allowing for even more advanced application development to share with customers. Sharing these projects internally can

have knock-on effects that help to deliver new innovations or open new possibilities for research and product development. In Veryst’s experience, customers ‘realise how the model is useful to them, want to use it internally, and then see how an application can help them do that,’ commented Elabbasi. ‘In short, the use of apps allows non-

experts to use simulations, and therefore design teams can either delegate work, or invite other decision-makers or teams. I think that is enabling both the simulation experts and other engineers in the design and development teams’ comments Sjodin. FEA software also impacts the

development of digital twins which are digital representations of a product

“FEA could provide quantitative tools to consider factors such as comfort, which are subjective and difficult to measure”

used to reduce the number of physical prototypes and reduce time to market for new components. In an article published in ABB Review in 2018, ABB, a specialist in digital technologies for industry worked with Comsol on a project that used FEA simulation as part of an approach to developing digital twins for Electromagnetic Flowmeters. ABB has developed a software model of an EM flowmeter based on a multiphysics finite element analysis (FEA) technique. This software model, or digital twin, is a replica that represents the physical asset in the virtual world, thereby mimicking the physical asset’s real behavior. Performance complexities can be understood, problems can be detected, and designs can be improved based on the resultant acquired process knowledge. In this case the use of FEA modelling, instead of using conventional testing

means that complex processes can be easily understood. The paper reports that FEA simulation coupled with reductions in the cost of high-performance computing (HPC) allow ‘diverse and complex’ physics- based equations to be easily and iteratively solved using FEA. The researchers found that the digital

twin technology can also be employed as a useful guide for flowmeter installation in the field, which enables industries such as water management facilities to improve their flow control systems in the interest of enhancing industrial process performance. The paper states that ‘the effect of

flow modification on measurement accuracy was studied to provide insight into the impact of system features such as upstream bends. As a result, ABB could determine the best location to install flowmeters within a given piping system, thereby enabling the correction of flowmeter readings for an installed flowmeter.’ ‘The digital twin technology can also be employed to serve as a useful guide for flowmeter installation in the field, which enabled industries like water management facilities to improve their flow control systems in the interest of radically enhancing industrial process performance.’

FEA HELPS RESEARCHERS UNDERSTAND THE COMFORT OF PROSTHETICS

A study published in Nature in March 2020 looked at the influence of gait cycle loads on the stress which causes potential pain and discomfort for amputees. The paper entitled: ‘Influence of Gait Cycle Loads on Stress Distribution at The Residual Limb/Socket Interface of Transfemoral Amputees: A Finite Element Analysis’ aimed to use FEA simulations to better understand ‘the interaction between residual limb and socket when considering the dynamic loads of the gait cycle.’ The researchers used

data collected from fourteen transfemoral amputees, where their residual limbs, including soft tissues, bone and their sockets were reconstructed. The paper states that: ‘The

socket and the femur were defined as elastic materials, while the bulk soft tissues were defined as a hyper-elastic material. Each model included the donning, standing, and

gait cycle phase, with load and boundary conditions, applied accordingly.’ The research project

explored the influence of adding the dynamic loads related to the gait cycle and compared that against the ‘modelling of the static load equivalent to the standing position.’ Additionally, the paper researchers were trying to understand a possible correlation between ‘comfort and the location of peak load bearing at the residual limb/ socket interface.’ This allowed researchers to

estimate the comfort perceived by the patient based on the locations of maximum stress. The paper states that:

‘In lower limb amputees, specifically for limb amputations above knee level, the prosthetic system consists mainly of a prosthetic foot, a prosthetic knee and a socket. Since the attachment between the residual limb and the

prosthesis occurs through the socket, its coupling is critical for patients looking to regain their functional mobility and perceived comfort. Among others, the main task of the socket is to distribute the loads applied on the residual-limb/ socket interface. By doing this, the stresses generated at the residual limb in sensitive areas are reduced.’ When wearing a prosthesis,

both normal (i.e., perpendicular to the skin) and shear stresses (i.e., tangential to the skin) are applied to the soft tissues of the residual limb, which are not accustomed to bear such elevated loads, inducing the risk of skin problems and chronic pain This study focused on the

differences in residual-limb stress distribution, when different types of loads are applied (static vs dynamic) to a FEA of transfemoral amputees, especially on maximum pressure distribution.

By including dynamic loads in the FEA for transfemoral amputees, specifically the complete gait cycle, the researchers found that it was possible to provide a ‘complete view of how stresses and the areas affected at each moment change.’ This provides practical values that will support better decisions in future patient rehabilitation. The paper goes on to state

that for future research ‘FEA could provide quantitative tools to consider factors such as comfort, which are subjective and difficult to measure. ‘For example, the

development of a valid and reliable model that can relate comfort perception to the stresses generated at the residual limb by the strains created through socket design. The model could lead to the quantitative definition of the amount of rectification that amputees can bear according to their comfort threshold.’